Drill boom structure

ABSTRACT

A feed bar for guiding a rock drill is swingably carried at the end of a swingably mounted boom. Besides being laterally and vertically swingable on the boom, the feed bar is swingable about an axis parallel with its longitudinal axis.

United States Patent [72] Inventors Pieter Barendsen Knivsta; Carl OlovLindgren, Nacka; Erich Valdemar Kimber; Karl Erik Qvarnstrom, Vendelso,Sweden [21] Appl. No. 805,638 [22] Filed Mar. 10,1969 [45] Patented Feb.16, 1971 [73] Assignee Atlas Copco Aktiebolag Nacka, Sweden [3 2]Priority Mar. 12, 1968 [33] Sweden [31 3236/68 [54] DRILL BOOM STRUCTURE7 Claims, 9 Drawing Figs.

[52] US. Cl 173/43,

173/38 [51] lnt.Cl E21c 11/02 [50] Field ofSearch 173/43, 44, 38;299/72; 248/16 [56] References Cited I UNITED STATES PATENTS 3,020,0122/1962 Moracco et a] l73/43X 3,226,064 12/1965 Thompson... l73/43X3,333,646 8/1967 Hoen et al. 173/38X Primary Examiner- Ernest R. PurserAtmrney- Eric Y. Munson ABSTRACT: A feed bar for guiding a rock drill isswingably carried at the end of a swingably mounted boom. Besides beinglaterally and vertically swingable on the boom, the feed bar isswingable about an axis parallel with its longitudinal axis.

PATENTED F581 6 1971 SHEET 3 [1F 3 I-IPIR' Y.

DRILL BOOM STRUCTURE This invention relates to swingably mounted drillboom structures of the type provided with a boom head for positioning acarrier of a feed bar for a rock drill into various angular positionswith respect to a working surface.

Such drill booms mounted onamobile substructure are usually used fordrilling parallel holes in a working surface such a: tin end wall of atunnel. When the feed bar is tiltable and laterally pivotable only, theboom itself will be an obstacle to positioning the feed bar to somepositions. That is to say, there will be a blind area" injthe workingsurface. If the feed bar is displaceable with respect to the boom, thisblind area is lessened or completely avoided.

For this reason, some previous booms of this type have been equippedwith means for turning or rotating the boom head on the boom. In theseprevious embodiments thefeed bar does not remain in its angulardirection during turning unlessit is in a specific position with respectto the boom. Therefore, the feed bar must normally be repositionedmanually after a tummg. I

It is an object of the invention to provide a drill boom structure ofthe above-stated type which has the feed bar displaceable with respectto the boom in such a way that the boom remains in its angular directionwhen it is displaced.

For these and other purposes; there is provided a drill boom structurecomprising a boom arranged-at one end for lateral and vertical swingingon a substructure, a boom head at the opposite end of said boom arrangedon said boom for motor actuated swinging about a first axis, a carrierpivotably mounted on said boom head for swinging about a second axisperpendicular to said first axis, and-afeed bar for guiding a rock drillin a feeding direction mounted on said carrier, said carrier comprisinga motor actuated hinge means for swinging said feed bar about athirdaxis, which is perpendicular to said second axes and parallel withsaid feeding direction.

The above and other objects of the invention are obvious from thefollowing description and the accompanying drawings in which fourpreferred e'mbodiments of the invention are illustrated by way ofexample. It should be understood that these embodiments are onlyvillustrative of the invention and that various modifications may be madewithin the scope ofthe claim.

The invention is described with reference to the drawings in which FIG.1 is a horizontal view, partly in section, of the outer part of a drillboom structure according to the invention, FIG. 2 is a section of line2-2 in FIG. 1, FIG. 3 is an end view on line 3-3 in FIG. 1, FIG. 4 is asection of a hydraulic lock, which in FIG. 1 is shown applied to theboom structure, FIGS. 5 and 6 are vertical views of two modified drillboom struc tures according to the invention, FIG. 7 is an end view online 7-7 in FIG. 6, FIG. 8 is an end view of a modified form of the boomstructure shown in FIGS. 6 and 7, and FIG. 9 is a horizontal view of theboom structure in FIG. 8. In all the FIGS. corresponding details aregiven the same reference numeral.

In FIGS. 1-3 there is shown the outer end of a boom 10, which islaterally and vertically swingable by means of suitable hydrauliccylinders, which are not shown. On a boom head 11 on the boom 10, thereis mounted a carrier 12 for a feed bar 13 guiding a rock drill 14. Theboom head 11 is tiltable on a horizontal pivot 15 by means of a rod 17in a way as will be described with reference to FIG. 5. Laterally, thefeed bar carrier 12 pivots on a pivot 16 by means of a hydraulic swingcylinder 19.

The rock drill 14 is slidably mounted on the feed bar 13 and fed by achain feed means 20 (FIG. 2) in a well known manner. The feed bar itselfis axially slidably mounted on a plate 22 which is made rigid by meansof side plates 21. A feed bar mover in the form of a hydraulic cylinder23 provides the axial movement of the feed bar. The plate 22, which is apart of the carrier 12, is affixed to an end part or journal member 24,which embraces one end of a casing 25 for a turning means or motor meansand is rotatably journaled on the casing 25. The cylinder 19 forswinging the carrier 12 on the boom head 11 is connected to a support 31screwed to the casing 25, which by means of lugs 27 is mounted on thevertical pivot 16. The plate 22 is fixed also to the upper half of anaxially divided sleeve or journal member 26, which is journaled on thecasing 25 and axially fixed by a stop lug 28 and a flange 29 on theeasing 25. The casing 25 and the journal members 24, 26 thus provide ahinge means for swinging a part 24, 26, 21, 22 of the carrier withrespect to another part 25, 31 of the carrier. In FIG. 3, the feed bar13 is shown turned into two alternative positions.

In the turning means 30, FIG. 1 there is generated torque by a drivescrew 32 which by helical splines is in engagement with correspondingsplines in a turning nut 33. The drive screw 32 forms a piston rod of apiston 34, which is slidably and sealingly guided in a cylinder sleeve35. The cylinder sleeve 35 is affixed by screws to a cylindrical basehead 36 into which the piston 34 projects slidingly but nonrotatablywith a piston rod 37 provided with straight splines cooperating withcorresponding splines in the head 36. The head 36 is screwed to the endflange 29 of the casing 25 and is closed by a cover 38.

The cylinder sleeve 35 fixedly carries a bearing member 40 in which adriving member 41 is rotatably journaled. The driving member is carriedby a radial ball bearing 42 and is fixed axially at a central flange 43between two axial ball bearings 44. The bearing member 40 and itsbearings 42, 44 are covered by a cover 45 screwed to the bearing member40 and sealed by suitable rings with respect to the rotatable drivingmember 41. At the end of a hollow member 46 of the driving member whichprojects into the drive end of the cylinder sleeve 35 the driving member41 carries the turning nut 33.

A splined end 47 of the driving member 41 protruding from the cover 45mates with splines in the end part 24 for rotating the latter. To thebearing member. 40 is connected a pressure fluid conduit 48 by means ofwhich pressure fluid can be supplied via suitable interior channels andopenings in the bearing member 40 to the drive end of the cylindersleeve 35 and to the interior of the hollow member 46 via bores in thedriving member 41. By means of another pressure fluid conduit 49pressure fluid can be supplied via suitable interior channels in thebase head 36 to the base end of the cylinder sleeve 35 and the interiorof the head 36. The conduits 48, 49 are connected to a hydraulic lockmeans which by means of conduits 48", 49" is connected in a conventionalmanner to a source of hydraulic pressure, not shown, via a control valvepreferably of four way type and likewise not shown which closes theconduits 48", 49 or opens one of them optionally to high pressure andthe other for return flow.

When pressure fluid is supplied to the conduit 49', the cylinder chamberat the base end of the cylinder sleeve 35 is pressurized as well as theinterior of the base head 36. As a result the piston 34 is moved fromthe base head 36 by pressure acting upon the piston and upon the pistonrod 37 simultaneously with pressure fluid in front of piston 34 anddrive screw 32 being expelled via the conduit 48 and the drive screw 32urging rotation of the nut 33. Thus the driving member 41 is forced torotate in the bearing member 40 and its rotation is transmitted by itssplines to the end part 24 so that the feed bar 13 can be adjusted tothe desired angle about the longitudinal axis of the driving member.During angular adjustment, reaction torque caused by the torquegenerated between the drive screw 32 and the turning nut 33 istransmitted via the splines of the piston rod 37 to the base head 36 andthereby to the casing 25 and the boom head 11. Obviously, when pressurefluid is supplied to the conduit 48 the drive end of the cylinder sleeve35 and the interior of the hollow member 46 of the driving member 41 arepressurized. This causes return of the piston 34with its drive screw 32and piston rod 37 simultaneously with pressure fluid being expelled fromthe base end of the cylinder sleeve 35 and the interior of the base head36 via the conduit 49'.

In order to increase the torsional rigidity of the hinge means in thevarious adjusting positions thereof, there is used a hydraulic lockmeans 50 working on spring loaded check valves 51, 52, FIG. 4. The checkvalves 51, 52 take up closed position and prevent return flow from theconduits 48', 4 9 when low pressure is maintained in the conduits 48",49"and the control valve, not shown, is in neutral position. Thus thepiston 34 will be retained rigidly and hydraulically arrested in anyadjusted position between one end position in which it abuts against thebase head 36 and the other end position in which it abuts against thehollow member 46. As soon as high pressure is admitted to any of theconduits 48"or 49*by actuation of the control valve, a piston slide 53slidably inserted in the hydraulic lock 50 between said conduits 48",49"opens by the aid of a pushing rod and by way of forced motion theparticular check valve 51 and 52'which is to be passed by return flow tothe other conduits 49"or 48".

In FIG. 5, there is shown a boom structure having a boom of the typeshown in FIG. 1. The feed bar carrier, the turning means and otherdetails are principally as described with reference to FIG. I, but theboom head I1 is modified so that the feed bar carrier 12 is arrangedvertically off set the boom 10 instead of laterally off set. By the aidof the swing cylinder 19, the feed bar carrier 12 may be swung on thepivot 16. Normally, this pivot is vertical but it may be tilted togetherwith the boom head II on the horizontal-pivot 15 by lengthening orshortening the rod 17 by means of a hydraulic cylinder 18 integral withthe rod 17. The boom is universally swingable on suitable pivots bymeans of cylinders 56, 57. Reference numeral 58 refers to a substructureor boom support. During vertical swinging of the boom 10, the boom head11 and thus the feed bar 13 will maintain its angular position byvirtueof the rod 17. Such a parallel movement can also be provided by virtueof hydraulic control means, e.g. as described in US. Pat. No. 2,613,822.v

In FIG. 6 there is shown another design in which the boom 10 comprises afirst boom portion 10 and a second boom portion I", The second andforked boom portion is telescopically and extendably carried by thefirst boom portion. A rod 17, as described, is therefore not suitablebut the boom head is tiltable by means of a hydraulic cylinder 59. Inthis embodiment, the feed bar is mounted on two arms 60 on the journalmembers 24, 26. The mounting of the carrier 12 on the boom head 11compares favorable with the arrangements shown in the preceding figuresby permitting the hinge means 24, 25, 26 to turn at least 270. At thearm of member 26, the feed bar is pivotally mounted on a transversepivot, not shown, and at the arm of member 24 it is mounted by means ofa hydraulic cylinder 61. By this arrangement the feed bar may beadjusted out of alignment with the hinge means so that the outermostholes in an end wall of a tunnel may be directed for instance aboutoutwardly with respect to the other holes which normally are paralleland directed perpendicular to the end wall. In FIG. 89 there is shown amodified form of the drill boom in FIG. 67. In this embodiment there isa first hinge means arranged for swinging the arms 60 as described. Thishinge means is given reference numeral 62. The arms, however, carries asecond hinge means 63 for turning the feed bar 13 with respect to thearms. The feed bar may be mounted on the second hinge means by means ofa hydraulic cylinder 61 as described with reference to FIGS. 67.

Although several embodiments of the invention have been illustrated anddescribed in detail, it is to be understood that the invention is notlimited thereto.

We claim:

l. A drill boom structure comprising a boom arranged at one end forlateral and vertical swinging on a substructure, a boom head at theopposite end of said boom arranged on said boom for motor actuatedswinging about a first axis, a carrier pivotably mounted on said boomhead for swinging about a second axis perpendicular to said first axis,and a feed bar for guiding a rock drill in a feeding direction mountedon said carrier, said carrier comprising a motor actuated hinge meansfor swinging said feed bar about a third axis, which is perpendicular tosaid second axes and parallel with said feeding direction. 2. A drillboom structure accordmg to claim I III WhlCh a motor means for actuatingsaid hinge means includes a pressure fluid actuated piston, which issealingly guided for reciprocation in a cylinder and has piston rodmeans slidingly connected to a first member of the carrier by a splinedconnection and piston rod means slidingly connected to a second memberof the carrier by a splined connection having screw splines, said firstand second member of the carrier being rotatively journaled to eachother for providing the hinge means.

3. A drill boom structure according to claim 2 in which said first partof the carrier comprises a cylindrical housing for the motor meansmounted on said boom head and said second part of the carrier comprisesa support rotatably journaled on said cylindrical housing, said supportextendably carrying the fed bar.

4. A drill boom structure according to claim 1 in which the boomcomprises a first boom portion, which is mounted on the substructure,and a second boom portion, which is parallel with and extendablysupported by said first boom portion and carries the boom head.

5. A rock drill boom structure comprising a boom havingone enduniversally pivotally connected to a mounting, a boom head pivotallymounted at the opposite end of the boom for swinging about a firstaxis,- a first member pivotally mounted on the boom head for swingingabout a second axis, which is perpendicular to said first axis, a secondmember swingably carried by said first member for swinging about a thirdaxis, which is perpendicular to said second axes, a feed bar for a rockdrill which is extendably supported by said second member and has alongitudinal axis substantially parallel to said third axis, motor meansfor swinging the boom laterally and vertically relative to saidmounting, a motor means for swinging the boom head about said firstaxis, a motor means for swinging said first member about said secondaxis, and a motor means for swinging said second member about said thirdaxis.

6. A rock drill boom structure comprising a boom arranged at one end forlateral and vertical swinging on a substructure, a boom head at theopposite end of said boom arranged on said boom for motor actuatedswinging about a first pivot providing means, a carrier pivotablymounted on said boom head for swinging about a second pivot providingmeans, which is perpendicular to said first pivot providing means, and afeed bar for guiding a rock drill mounted on said carrier, whichcomprises a first motor actuated hinge means arranged on said head and asecond motor actuated hinge means swingably carried by said first hingemeans and swingably carrying said feed bar, said first and second hingemeans and the feed bar being substantially parallel to each other butperpendicular to said first and second pivot providing means.

7. A rock drill boom structure comprising a boom connected at one end toa substructure so as to be pivotal about a horizontal axis and about avertical axis, motor means for swinging said boom about said horizontalaxis, motor means for swinging said boom about said vertical axis, aboom head at the opposite end of the boom, a first hinge means arrangedon said head, a second hinge means swingably carried by said first hingemeans and arranged laterally thereof, and a feed bar for guiding a rockdrill swingably carried by said second hinge means, the axes of thefirst and second hinge means and said feed bar being substantiallyparallel.

1. A drill boom structure comprising a boom arranged at one end forlateral and vertical swinging on a substructure, a boom head at theopposite end of said boom arranged on said boom for motor actuatedswinging about a first axis, a carrier pivotably mounted on said boomhead for swinging about a second axis perpendicular to said first axis,and a feed bar for guiding a rock drill in a feeding direction mountedon said carrier, said carrier comprising a motor actuated hinge meansfor swinging said feed bar about a third axis, which is perpendicular tosaid second axes and parallel with said feeding direction.
 2. A drillboom structure according to claim 1 in which a motor means for actuatingsaid hinge means includes a pressure fluid actuated piston, which issealingly guided for reciprocation in a cylinder and has piston rodmeans slidingly connected to a first member of the carrier by a splinedconnection and piston rod means slidingly connected to a second memberof the carrier by a splined connection having screw splines, said firstand second member of the carrier being rotatively journaled to eachother for providing the hinge means.
 3. A drill boom structure accordingto claim 2 in which said first part of the carrier comprises acylindrical housing for the motor means mounted on said boom head andsaid second part of the carrier comprises a support rotatably journaledon said cylindrical housing, said support extendably carrying the fedbar.
 4. A drill boom structure according to claim 1 in which the boomcomprises a first boom portion, which is mounted on the substructure,and a second boom portion, which is parallel with and extendablysupported by said first boom portion and carries the boom head.
 5. Arock drill boom structure comprising a boom having one end universallypivotally connected to a mounting, a boom head pivotally mounted at theopposite end of the boom for swinging about a first axis, a first memberpivotally mounted on the boom head for swinging about a second axis,which is perpendicular to said first axis, a second member swingablycarried by said first member for swinging about a third axis, which isperpendicular to said second axes, a feed bar for a rock drill which isextendably supported by said second member and has a longitudinal axissubstantially parallel to said third axis, motor means for swinging theboom laterally and vertically relative to said mounting, a motor meansfor swinging the boom head about said first axis, a motor means forswinging said first member about said second axis, and a motor means forswinging said second member about said third axis.
 6. A rock drill boomstructure comprising a boom arranged at one end for lateral and verticalSwinging on a substructure, a boom head at the opposite end of said boomarranged on said boom for motor actuated swinging about a first pivotproviding means, a carrier pivotably mounted on said boom head forswinging about a second pivot providing means, which is perpendicular tosaid first pivot providing means, and a feed bar for guiding a rockdrill mounted on said carrier, which comprises a first motor actuatedhinge means arranged on said head and a second motor actuated hingemeans swingably carried by said first hinge means and swingably carryingsaid feed bar, said first and second hinge means and the feed bar beingsubstantially parallel to each other but perpendicular to said first andsecond pivot providing means.
 7. A rock drill boom structure comprisinga boom connected at one end to a substructure so as to be pivotal abouta horizontal axis and about a vertical axis, motor means for swingingsaid boom about said horizontal axis, motor means for swinging said boomabout said vertical axis, a boom head at the opposite end of the boom, afirst hinge means arranged on said head, a second hinge means swingablycarried by said first hinge means and arranged laterally thereof, and afeed bar for guiding a rock drill swingably carried by said second hingemeans, the axes of the first and second hinge means and said feed barbeing substantially parallel.